Till now there was not really I way to update mods. There has always been a system to upload new versions but no way to update them. The update process only happened when u joined a game with a newer version. To make sure that players do not play old outdated versions the client will beginning from the next update pull the newest version when hosting. Updated is only what is currently selected for the game being hosted.
The corresponding change: https://github.com/FAForever/downlords-faf-client/pull/2255
It can be turned off but is on by default.
For modders that means:
- Be aware that if you push new version that should be working because now ppl acctually get to play them.
- If you have a mod that has a huge download size, you should consider bundling changes so you maybe update at most once a month to avoid traffic for users(there is almost no mod that this applies to)